Mat boards with cut sight openings are commonly used for framing photographs, pictures and the like. Numerous forms of manual devices and machines are disclosed in the art, and are commercially available in both professional and also "DIY" (do-it-yourself) models, for cutting both the outside periphery of such mats (normally done with a "straight" cut, at a perpendicular angle) as well as the sight opening (normally done with a "bevel" cut, at an acute angle).
Exemplary apparatus is shown in the following U.S. patents: Williams U.S. Pat. No. 1,250,538, issued Dec. 18, 1917, Umholtz U.S. Pat. No. 2,924,010, issued Feb. 9, 1960, Meshulam et al U.S. Pat. No. 4,064,626, issued Dec. 27, 1977, Pierce U.S. Pat. No. 4,262,419, issued Apr. 21, 1981, Beder U.S. Pat. No. 4,685,366, issued Aug. 11, 1987, and McGinnis U.S. Pat. No. 4,986,156, issued Jan. 22, 1991; a system generally more sophisticated than the foregoing is disclosed by Kozyrski et al in U.S. Pat. No. 4,798,112, issued Jan. 17, 1989. Davidson U.S. Pat. No. 4,831,739, issued May 23, 1989, provides an adjustable template device, for framing and cutting sheet material, in which resilient pins engage lines of detents so as to retard relative sliding movement of adjacent members.
Despite the foregoing, a need remains for a manual cutter which is capable of operating in both of two opposite directions, which affords a wide degree of flexibility of use, and which is, at the same time, of relatively simple and inexpensive construction and hence particularly well adapted for sale as a DIY cutter.